Undo "Temporarily remove the pack.mcmeta check"

Author: Novampr

converter/src/main/java/org/geysermc/pack/converter/PackConverter.java

@@ -297,11 +297,10 @@ public PackConverter convert() throws IOException {
         VanillaPackProvider.create(vanillaPackPath, this.logListener);
 
         ZipUtils.openFileSystem(this.input, this.compressed, input -> {
-            // TODO: Add this back as an optional thing in API once it's been sorted out
-//            if (!Files.exists(input.resolve("pack.mcmeta"))) {
-//                logListener.error("Invalid Java Edition resource pack. No pack.mcmeta found.");
-//                return;
-//            }
+            if (!Files.exists(input.resolve("pack.mcmeta"))) {
+                logListener.error("Invalid Java Edition resource pack. No pack.mcmeta found.");
+                return;
+            }
 
             this.tmpDir = this.output.toAbsolutePath().getParent().resolve(this.output.getFileName() + "_mcpack/");